Can i cancel my federal taxes for 2016

[DoninGA]

Have you already e-filed the federal tax return?

[null14]

Yes

[jerry2000 · Accepted solution]

If you have not yet filed, then just stop using Turbotax and don't complete your return.
If you have already filed, then,
Submitting the return for filing is just like dropping it into a mailbox - you can not get it back or change it.

Once you submit  and find that you need to make a change, you will have to wait until the IRS either accepts or rejects the return. If the return is rejected by the IRS, then you can make the necessary changes and resubmit it. If the return is accepted, then the only way to change it is to prepare an amended return and file it by mail.